Michael "Mike" Maguire, 21, originally from County Cork, Ireland, was hit in the temple by a single machine gun bullet fired by a fellow soldier training one kilometre away.

He was relaxing in a designated safe haven at the sprawling Castlemartin Ranges, along the Pembrokeshire coast, in May last year. The ranger, with the 1st Battalion, The Royal Irish Regiment, had taken off his body armour and protective helmet after finishing his own live fire training.

A two-week inquest in Cardiff into the circumstances surrounding his death highlighted a series of potentially fatal failings.

Range commander Lieutenant Jonathan Price dismissed suggestions while giving evidence that he had failed to fully take up his responsibilities. But the jury heard that a risk assessment was not fully carried out and attack targets were found to be wrongly placed.

Family members were more scathing in their criticism after the unlawful killing verdict.

Jimmy Maguire, the dead ranger's older brother, said: "We are surprised and puzzled how somebody could have been considered competent to conduct an exercise of this nature when at the same time he made so many fundamental errors, and how this could not have been picked up through the chain of command and at the range. We are left wondering how someone with such limited experience could have been put in charge of the training exercise and the range with no senior officer present and without appropriate supervision."

He added: "However, we are disappointed that key personnel involved decided to rely on their right not to answer questions which were potentially self-incriminating rather than gave the inquest a full and true account of what happened. That has left us with unanswered questions, in particular about the actions of the people responsible for the planning of and safety on the exercise that caused Mike's death."

He said the family hoped other continuing inquiries into the death, by the Health and Safety Executive and the Army itself, would eventual supply the answers to their questions.